script to tail file; problem with awk and special characters

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# 1  
script to tail file; problem with awk and special characters

Trying to use code that I found to send only new lines out of a log file by doing:
while :; do
temp=$(tail -1 logfile.out)
awk "/$last/{p=1}p" logfile.out  #pipe this to log analyzer program
sleep 10

Script works fine when logfile is basic text, but when it contains characters that have brackets and slashes, the awk command has issues:
awk: fatal: Invalid range end: /[15C8:01E6-0258] 01/

Here is sample data in log:
[15C8:01EB-1DF8] 01/24/2012 08:03:43 AM Open session 
[15C8:01EB-0310] 01/24/2012 08:03:43 AM  Closed session 
[11A8:000F-06F4] 01/24/2012 08:03:44 AM  Router: Message 0047BCE8 delivered to
[15C8:01EB-1660] 01/24/2012 08:03:44 AM  Opened session 
[15C8:01E6-0258] 01/24/2012 08:03:44 AM  Closed session for

I have tried different ways of putting quotes around the last variable, but does not work or breaks script in different way. Any awk experts have suggestions?

Thx. Moo.

Moderator's Comments:
Mod Comment How to use code tags

Last edited by Franklin52; 01-24-2012 at 11:59 AM.. Reason: Please use code tags for code and data samples, thank you
# 2  
Another way :
while :
    Line=$(wc -l < moo.txt)
    awk "NR>$Last {p=1}p" moo.txt #pipe this to log analyzer program
    sleep 10

This User Gave Thanks to aigles For This Post:
# 3  
thx jean-Pierre. I added the if statement to your code to handle if log file gets truncated/rolled/etc....
while : do     
Line=$(wc -l < moo.txt)
    if [ $Line -lt $Last ]     
    awk "NR>$Last {p=1}p" moo.txt #pipe this to log analyzer program     
sleep 10 

Last edited by Franklin52; 01-25-2012 at 04:52 AM.. Reason: Please use code tags for code and data samples, thank you
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